[PATCH] libnm: Check the priv pointer before loop traverse.

["Shih-Yuan Lee (FourDollars)" <sylee canonical com>]

When we used WWAN and enabled the PIN on SIM, we encountered the following
crash during the stress suspend&resume test.

This patch can avoid this crash.

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Reading symbols from /usr/bin/nm-connection-editor...(no debugging symbols found)...done.
warning: core file may not match specified executable file.
[New LWP 1895]
[New LWP 1896]
[New LWP 1898]
[New LWP 1897]
[New LWP 1899]
warning: Could not load shared library symbols for 2 libraries, e.g. 
/usr/lib/x86_64-linux-gnu/liblttng-ust-tracepoint.so.0.
Use the "info sharedlibrary" command to see the complete listing.
Do you need "set solib-search-path" or "set sysroot"?
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
Core was generated by `/usr/bin/nm-connection-editor'.
Program terminated with signal SIGSEGV, Segmentation fault.
#0  recheck_pending_activations (self=0x193d220) at nm-manager.c:824
warning: Source file is more recent than executable.
824             for (iter = priv->devices; iter; iter = iter->next) {
[Current thread is 1 (Thread 0x7f3c4197fa80 (LWP 1895))]
(gdb) bt
#0  recheck_pending_activations (self=0x193d220) at nm-manager.c:824
#1  0x00007f3c400cbfa5 in g_closure_invoke () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#2  0x00007f3c400ddfc1 in ?? () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#3  0x00007f3c400e6d5c in g_signal_emit_valist () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#4  0x00007f3c400e708f in g_signal_emit () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#5  0x00007f3c400d04d4 in ?? () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#6  0x00007f3c400d2961 in g_object_notify () from /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#7  0x00007f3c406e3e63 in deferred_notify_cb (data=<optimized out>) at nm-object.c:252
#8  0x00007f3c3fdf4fda in g_main_context_dispatch () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#9  0x00007f3c3fdf5380 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#10 0x00007f3c3fdf56a2 in g_main_loop_run () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#11 0x0000000000414e81 in main ()
(gdb) l
819             if (!nm_settings_get_startup_complete (priv->settings)) {
820                     _LOGD (LOGD_CORE, "check_if_startup_complete returns FALSE because of NMSettings");
821                     return;
822             }
823     
824             for (iter = priv->devices; iter; iter = iter->next) {
825                     NMDevice *dev = iter->data;
826     
827                     if (nm_device_has_pending_action (dev)) {
828                             _LOGD (LOGD_CORE, "check_if_startup_complete returns FALSE because of %s",
(gdb) print priv
$1 = (NMManagerPrivate *) 0x0

Shih-Yuan Lee (FourDollars) (1):
  libnm: Check the priv pointer before loop traverse.

 libnm/nm-manager.c | 2 ++
 1 file changed, 2 insertions(+)

-- 
2.7.4